Microsoft: KB5021233 causes blue screens with 0xc000021a errors

Microsoft is investigating a known issue leading to Blue Screen of Death (BSOD) crashes with 0xc000021a errors after installing the Windows 10 KB5021233 cumulative update released during this month’s Patch Tuesday. The company warned over the weekend that “after installing KB5021233, some Windows devices might start up to an error (0xc000021a) with a blue screen.”